Many widespread diseases are caused by or manifested in abnormalities in blood microcirculation. There is a pressing need for a noninvasive device to collect maximum information about the structure of the microcirculation network, the functional parameters of blood microcirculation such as a blood flow velocity and blood oxygen saturation, and tissue morphology. To satisfy this need, Physical Optics Corporation (POC) proposes to develop a new multiwavelength optical coherent Doppler tomography (MOCDOT) microscope capable of 3D visualization of tissue morphology to a depth up to several millimeters, and of separate visualization of the microvascular network with measurement of the blood flow velocities in each component of this network and of arteriolar blood oxygenation. These multiple functions will be achieved by the unique combination of en-face optical coherence tomography with heterodyne measurements of the Doppler shift induced by light scattering by moving red blood cells. In Phase I, POC will fabricate a prototype of the MOCDOT microscope, and will demonstrate the performance on a chick embryo. After evaluating the test results, POC will optimize the MOCDOT design in preparation for developing a Phase II working prototype for clinical testing on patients who might have diabetic microangiopathy. [unreadable] [unreadable]